U.S. patent number 6,590,364 [Application Number 09/878,448] was granted by the patent office on 2003-07-08 for power kit assembly for a height adjustable chair.
This patent grant is currently assigned to EAC Corporation. Invention is credited to Robert A. Eberle, Joseph M. Mooney, M. Weldon Rogers, III, David L. Schwartz.
United States Patent |
6,590,364 |
Rogers, III , et
al. |
July 8, 2003 |
Power kit assembly for a height adjustable chair
Abstract
A power kit assembly for an adjustable chair that provides power
to a height adjustment mechanism to enable a chair to be adjusted
electrically in a cost effective and reliable manner is described.
The chair includes a limit switch that limits an amount of movement
of the height adjustment mechanism. The power kit assembly includes
a battery pack electrically and removably coupled to an electric
motor and to the limit switch. The electric motor is coupled to the
height adjustment mechanism. The battery pack includes at least one
battery cell and a housing. The battery cells are axially-aligned
within the battery pack housing and extend between first and second
ends of the housing. The battery cells are also rechargeable.
Inventors: |
Rogers, III; M. Weldon (St.
Louis, MO), Eberle; Robert A. (Kansas City, MO), Mooney;
Joseph M. (Florissant, MO), Schwartz; David L. (Creve
Coeur, MO) |
Assignee: |
EAC Corporation (St. Louis,
MO)
|
Family
ID: |
27401014 |
Appl.
No.: |
09/878,448 |
Filed: |
June 11, 2001 |
Current U.S.
Class: |
320/107;
297/217.3; 297/344.2 |
Current CPC
Class: |
A47C
1/023 (20130101); A47C 1/0242 (20130101); A47C
3/20 (20130101); A47C 3/24 (20130101); Y10T
29/49716 (20150115); Y10T 29/49721 (20150115) |
Current International
Class: |
A47C
1/025 (20060101); A47C 1/024 (20060101); A47C
1/022 (20060101); A47C 3/24 (20060101); A47C
3/20 (20060101); H01M 010/46 () |
Field of
Search: |
;320/107,112,113
;297/217.1,217.3,217.5,217.7,344.17,344.23,344.2 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Tso; Edward H.
Attorney, Agent or Firm: Reeser, III; Robert B. Armstrong
Teasdale LLP
Parent Case Text
CROSS REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application
No. 60/257,066 filed Dec. 20, 2000, and U.S. Provisional
Application No. 60/263,407 filed Jan. 23, 2001.
Claims
What is claimed is:
1. A power kit assembly for a chair including a height adjustment
mechanism including a limit switch configured to limit an amount of
movement of the height adjustment mechanism, said power kit
assembly comprising: an electric motor coupled to the height
adjustment mechanism; and a battery pack electrically coupled to
said electric motor and to the limit switch, said battery pack
configured to supply power to said electric motor for adjusting a
height of the chair with the height adjustment mechanism, said
battery pack comprising at least one battery cell, and a housing,
said battery cell extending from a first end of said battery pack
to a second end of said battery pack, said housing defining a
cavity, said battery pack within said housing cavity.
2. A power kit assembly in accordance with claim 1 wherein said
battery pack battery cell is rechargeable.
3. A power kit assembly in accordance with claim 1 wherein said
battery pack battery cell comprises at least one of a lead acid
battery, a nickel metal hydride battery, a nickel cadmium battery,
a lithium ion battery, and a lithium ion polymer battery.
4. A power kit assembly in accordance with claim 1 wherein said
battery pack housing substantially cylindrical.
5. A power kit assembly in accordance with claim 1 wherein the
height adjustment mechanism includes a housing, said electric motor
within the height adjustment mechanism housing, said battery pack
removably coupled to the height adjustment mechanism housing.
6. A power kit assembly in accordance with claim 5 wherein said
battery pack further comprises at least one locking tab configured
to secure said battery pack to the height adjustment mechanism
housing.
7. A power kit assembly in accordance with claim 5 wherein the
battery pack further comprises a housing, said electric motor
within the height adjustment mechanism housing, said battery pack
housing within the height adjustment mechanism housing.
8. A power kit assembly in accordance with claim 1 wherein said
battery pack coupled to a battery life indicator configured to
detect an amount of useful life of said battery pack battery
cell.
9. A power kit assembly in accordance with claim 8 wherein said
battery life indicator provides at least one of an audible alarm
and a visual alarm.
10. A power kit assembly in accordance with claim 1 wherein a
rotation of said electric motor is reversible, such that said
electric motor further configured to increase and decrease a height
of the chair relative to a chair base.
Description
BACKGROUND OF THE INVENTION
This application relates generally to adjustable chairs, and more
particularly to height adjustment mechanisms used with adjustable
chairs.
Office chairs typically include a chair back, a chair seat, and a
base that supports the chair. The chair back is coupled to the
chair seat, and the chair seat is coupled to the chair base. More
specifically, a column extends between the base and the chair seat
to support the chair seat. At least some known chair bases include
casters or glides that enable the chair base to be in
freely-rollable or freely-glidable contact with a floor.
Sitting in a chair at an improper height for prolonged periods of
time may increase the discomfort and fatigue to the occupant. To
facilitate improving a comfort level of seated occupants, at least
some chairs include chair backs including adjustment mechanisms
that permit the chair back to be variably positioned with respect
to the chair seat, and permit the chair seat to be variably
positioned with respect to the chair base. More specifically, at
least some known chairs include an adjustable column that permits a
user to vary a height of the chair seat relative to the chair
base.
At least some known adjustable columns are coupled to the chair
seat with threaded connections. The threaded connections permit the
chair seat to rotate to adjust the relative height of the seat. As
a result, when an occupant rotates the chair seat relative to the
chair base, the height of the seat relative to the floor is
changed.
To permit rotation of the chair seat without adjustments being made
to the relative height of the chair, at least some other known
adjustable columns are rotatably coupled to the chair base with
swivel fixtures that permit the chair seat to rotate without
changing the height of the chair relative to the floor. Such
columns also include pneumatic cylinders which permit the relative
height of the chair to be manually changed. However, often the
adjustments can not be made while the occupant is seated, and as a
result, an adjustment process can be time-consuming and tedious as
the occupant must often make numerous trial adjustments finding a
chair seat position that is at a height relative to the floor that
is comfortable to the occupant.
SUMMARY OF THE INVENTION
In an exemplary embodiment, a power kit assembly for an adjustable
chair provides power to a height adjustment mechanism to enable a
chair to be adjusted electrically in a cost effective and reliable
manner. The chair includes a limit switch that limits an amount of
movement of the height adjustment mechanism. The power kit assembly
includes a battery pack electrically coupled to an electric motor
and to the limit switch. The electric motor is coupled to the
height adjustment mechanism. The battery pack includes a plurality
of battery cells and a housing. The battery cells are
axially-aligned within the battery pack housing and extend between
first and second ends of the housing. The battery cells are also
rechargeable.
During use, a seated occupant may electrically raise or lower the
chair seat relative to a chair base. When the electric motor is
activated, the battery pack supplies power to the motor. Because
the battery pack is removably coupled to the chair, when the power
supply to the batteries decreases after use, the battery pack may
be easily removed such that the battery cells may be recharged. As
a result, the battery pack supplies power to the electric motor in
a cost-effective and reliable manner.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is side view of an adjustable chair;
FIG. 2 is a partial cross-sectional side view of a height
adjustment mechanism that may be used with the chair shown in FIG.
1;
FIG. 3 is a partial cut-away side view of an alternative embodiment
of a height adjustment mechanism that may be used with the chair
shown in FIG. 1;
FIG. 4 is an enlarged cross-sectional view of the height adjustment
mechanism shown in FIG. 3 and taken along line 4--4;
FIG. 5 is a partial cut-away side view of an alternative embodiment
of a height adjustment mechanism that may be used with the chair
shown in FIG. 1;
FIG. 6 is a partial cut-away side view of an alternative embodiment
of a height adjustment mechanism that may be used with the chair
shown in FIG. 1;
FIG. 7 is an enlarged cross-sectional view of the height adjustment
mechanism shown in FIG. 6 and taken along line 7--7;
FIG. 8 is a cut-away side view of an alternative embodiment of a
height adjustment mechanism that may be used with the chair shown
in FIG. 1;
FIG. 9 is a side view of a battery pack that may be used with the
chair shown in FIG. 1;
FIG. 10 is cross-sectional view of the battery pack shown in FIG. 9
taken along line 10--10; and
FIG. 11 is a top view of the battery pack shown in FIG. 9.
DETAILED DESCRIPTION OF THE INVENTION
FIG. 1 is a side view of an adjustable chair 10. In one embodiment,
chair 10 is an office chair. Chair 10 includes a base 12, a seat
14, a back assembly 16, and a height adjustment mechanism 18. Chair
back assembly 16 is coupled to chair seat 14, and chair base 12
supports chair 10.
Chair base 12 is known in the art and is a pedestal support base
that includes a plurality of legs 20 arranged in a conventional
star-shaped arrangement. In one embodiment, base 12 includes five
legs 20. Alternatively, base 12 includes more or less than five
legs. Each leg 20 includes a caster 24, such that chair 10 is in
free-rolling contact with a floor (not shown). In an alternative
embodiment, chair legs 20 do not include casters 24.
Base legs 20 support chair 10 and extend from casters 24 to a
center socket 28. Socket 28 includes an opening (not shown in FIG.
1) extending therethrough and sized to receive height adjustment
mechanism 18. Height adjustment mechanism 18 extends through base
center socket 28, and is substantially perpendicular to base 12.
More specifically, height adjustment mechanism 18 extends between
base 12 and chair 10 and includes a drive mechanism (not shown in
FIG. 1) for adjusting a height 30 of chair seat 14 relative to
chair base 12.
FIG. 2 is a partial cross-sectional side view of a height
adjustment mechanism 40 that may be used with chair 10 shown in
FIG. 1. Height adjustment mechanism 40 includes an upper enclosure
member 42 telescopically coupled to a lower enclosure member 44.
More specifically, lower enclosure member 44 is coupled
substantially co-axially to upper enclosure member 42 such that
lower enclosure member 44 telescopes into upper enclosure member
42. Upper enclosure member 42 is coupled between chair seat 14
(shown in FIG. 1) and lower enclosure member 44. Lower enclosure
member 44 is coupled between upper enclosure member 42 and chair
base 12. In one embodiment, upper enclosure member 42 has a
substantially circular cross-sectional profile.
Upper enclosure member 42 includes a hollow guide sleeve 46, an
upper end 48, and a lower end 50. In addition, upper enclosure
member 42 includes an outer surface 52 and an inner surface 54.
Upper enclosure member upper end 48 is tapered to be frictionally
fit within a receptacle (not shown) extending from chair seat 14.
Upper enclosure member inner surface 54 defines a cavity 55 and
includes a plurality of threads 56 that extend radially inward from
inner surface 54 towards an axis of symmetry 58 for height
adjustment mechanism 40. Axis of symmetry 58 extends from upper
enclosure member first end 48 to upper enclosure second end 50.
Upper enclosure member threads 56 extend along inner surface 54
from upper enclosure member lower end 50 towards upper end 48. In
one embodiment, upper enclosure member 42 includes a spring (not
shown) mounted to provide a pre-determined amount of downward
travel of chair seat 14 when chair seat 14 is initially
occupied.
Upper enclosure member cavity 55 has a diameter 60 measured with
respect to inner surface 54 sized to receive lower enclosure member
44 therein. More specifically, lower enclosure member 44 is hollow
and includes an outer surface 62 including a plurality of threads
64 which extend radially outward from outer surface 62. In
addition, lower enclosure member 44 has an outer diameter 66 that
is smaller than upper enclosure cavity diameter 55. More
specifically, upper enclosure member cavity 55 and lower enclosure
member 44 are sized such that as lower enclosure member 44 is
received within upper enclosure member cavity 55, lower enclosure
member threads 64 engage upper enclosure member threads 66.
Lower enclosure member 44 also includes an inner surface 70 that
extends from an upper end 72 of lower enclosure member 44 to a
lower end 74 of lower enclosure member 44. Threads 64 extend
between upper and lower ends 72 and 74, respectively. Lower
enclosure member inner surface 70 defines a cavity 76 that has a
diameter 78 measured with respect to inner surface 70. A plurality
of threads 81 extend radially inward from inner surface 70 between
lower enclosure member upper and lower ends 72 and 74,
respectively.
Lower enclosure member 44 also includes an upper stop 81 and a
lower stop 82. Lower enclosure member upper stop 81 is adjacent
lower enclosure upper end 72. As lower enclosure member 44 rotates
within upper enclosure member 42, lower enclosure upper stop 81
contacts an upper enclosure member stop 84 to limit a distance that
upper enclosure member 42 may extend towards chair seat 14 from
chair base 12. Lower enclosure member lower stop 82 is adjacent
lower enclosure lower end 74 and limits a distance that lower
enclosure member 44 may extend towards chair seat 14 from chair
base 12. Stops 81 and 82 prevent height adjustment mechanism 40
from over-rotating as chair seat 14 is raised and becoming forcibly
stuck in a relative extended position that has exceeded a
pre-determined fully-extended position.
Lower enclosure member 44 is coupled to base 12 through a drive
mechanism 90. Drive mechanism 90 includes an electric motor 92, a
drive shaft 94, and a gear box 96. Electric motor 92 is coupled to
gear box 96 which in turn is coupled to drive shaft 94. Electric
motor 92 is known in the art and in one embodiment is commercially
available from Dewert Motorized Systems, Frederick, Md.,
21704-4300. More specifically, electric motor 92 and gear box 96
are coupled substantially perpendicularly to drive shaft 94. Drive
shaft 94 is substantially co-axial with respect to upper and lower
enclosure members 42 and 44, respectively.
Drive shaft 94 includes an outer surface 97 including a plurality
of threads 98 extending radially outward from outer surface 97.
Drive shaft 94 has an outer diameter 100 measured with respect to
outer surface 97 that is smaller than lower enclosure member cavity
diameter 78. More specifically, drive shaft diameter 100 is sized
such that when drive shaft 94 is received within lower enclosure
member 42, drive shaft threads 98 engage lower enclosure inner
threads 80. Drive shaft 94 also includes a stop 102 adjacent to an
upper end 104 of drive shaft 94. As drive shaft 94 rotates within
lower enclosure member 44, lower enclosure member 44 is rotated
within upper enclosure member 42 to raise or lower upper enclosure
member 42 with respect to chair base 12. When upper enclosure
member 42 is being raised, drive shaft stop 102 contacts lower
enclosure member lower stop 82 to limit a distance that lower
enclosure member 44 may extend towards chair seat 14 from chair
base 12. Drive shaft 94 also includes a lower end 104 coupled to
gear box 96. A load bearing 106 extends circumferentially around
drive shaft 94 between gear box 96 and lower enclosure member
44.
A hollow guide sleeve 110 extends circumferentially around upper
and lower enclosure members 42 and 44, and drive shaft 94. More
specifically, guide sleeve 110 is co-axially aligned with respect
to upper and lower enclosure members 42 and 44, and drive shaft 94,
and has a first end 112 and a second end 114. Guide sleeve 110 has
a height (not shown) such that guide sleeve first end 112 is
between upper enclosure member upper and lower ends 48 and 50,
respectively, and guide sleeve second end 114 is in proximity to
gear box 96, such that load bearing 106 is between guide sleeve
second end 114 and gear box 96.
Guide sleeve 110 also includes an anti-spin and side load collar
118, and an upper stop 120. During rotation of lower enclosure
member 44, guide sleeve upper stop 120 works in combination with
lower enclosure upper stop 81 and upper enclosure stop 84 to limit
a distance that upper enclosure member 42 may extend towards chair
seat 14 from chair base 12. Anti-spin and side load collar 118
includes channels (not shown) that extend lengthwise along guide
sleeve 110 to prevent guide sleeve 110 from rotating as chair seat
14 is rotated. More specifically, because upper enclosure member 42
is frictionally coupled beneath chair seat 14, as chair seat 14 is
rotated, upper enclosure member 42 rotates simultaneously with
chair seat 14, and induces rotation into lower enclosure member 44.
Anti-spin and side load collar 118 permits chair seat 14 to rotate
without permitting guide sleeve 110 to rotate. In addition, as an
occupant sits and moves around within chair seat 14, side loading
forces induced into upper and lower enclosure members 42 and 44,
respectively, are transmitted through guide sleeve 110 and
anti-spin and side load collar 118 into chair base 12.
Anti-spin and side load collar 118 extends around guide sleeve 110
between guide sleeve 110 and a housing 124. Housing 124 has an
upper surface 120 and a lower surface 122, and extends around guide
sleeve 110 and anti-spin and side load collar 118. Housing 124
includes an upper portion 126 and a lower portion 128. Upper
portion 126 is substantially circular and has an inner diameter 130
that is smaller than an outer diameter 132 of an opening 134
extending through base socket 28. Housing lower portion 128 has an
outer diameter 136 that is larger than base socket opening 134.
A plurality of sensors 140 are mounted to housing upper surface 120
and receive signals from a switch (not shown) attached to chair
seat 14. Sensors 140 detect when a pre-determined amount of
resistance is induced into height adjustment mechanism 40 as chair
seat 14 is raised. More specifically, sensors 140 are coupled to
drive mechanism 90 and stop operation of electric motor 92 when a
pre-determined amount of resistance is sensed. In one embodiment,
sensors 140 are infrared sensors and receive an infrared signal
transmitted from an infrared switch attached to chair seat 14. In a
further embodiment, sensors 140 are commercially available from
Dewert Motorized Systems, Frederick, Md., 21704.
Sensors 140 are coupled to a limit or resistance sensing switch
142. Limit switch 142 receives a signal from sensors 140 regarding
a relative position of drive shaft 94 measured with respect to
chair base 14. More specifically, limit switch 142 is electrically
coupled to electric motor 92 and automatically stops a flow of
electric current to motor 92 when drive shaft 94 nears a pre-set
fully extended position.
Drive mechanism 90 is housed within housing 124 and is electrically
coupled to a battery pack 144 including rechargeable battery cells
(not shown in FIG. 2). In the exemplary embodiment, battery pack
144 has a substantially rectangular cross-sectional profile.
Alternatively, battery pack 144 has a non-rectangular
cross-sectional profile. More specifically, a plurality of wires
146 couple battery pack 144 to electric motor 92 to permit battery
pack 144 to supply power to motor 92. In addition, electric motor
92 is also coupled to a resistance sensing switch (not shown) which
automatically stops a flow of electric current to motor 92 when a
pre-determined amount of resistance is induced within height
adjustment mechanism 40 as chair seat height 30 (shown in FIG. 1)
is adjusted. For example, the resistance sensing switch
automatically stops a flow of electric current to motor 92 to
prevent an occupant's legs (not shown) from being compressed
between chair seat 14 and an underside (not shown) of a desk or
table (not shown) as seat 14 is raised.
The battery pack battery cells are removably coupled within housing
124. In another embodiment, battery pack 144 is mounted separately
from housing 124 to facilitate removal and replacement of the
battery cells for recharging purposes. The battery cells may be,
but are not limited to, a lead acid battery, a nickel metal hydride
battery, a nickel cadmium battery, a lithium ion battery, or a
lithium ion polymer battery. In one embodiment, a battery life
indicator (not shown) is coupled to battery pack 144 to indicate
when a useful life of battery pack battery cells is decreasing and
requires recharging.
During assembly, height adjustment mechanism 40 is initially
assembled. More specifically, upper enclosure member 42 is coupled
to lower enclosure member 44, and the assembly is inserted within
housing 124. Limit switch 142 is coupled to either the upper
enclosure member 42 or the lower enclosure member 44, and to
electric motor 92.
Drive mechanism 90 is then coupled to lower enclosure member 44,
and inserted within housing 124. More specifically, gear box 96 is
coupled to drive shaft 94, and motor 92 is then coupled to gear box
96. Battery pack 144 is then coupled to motor 92 and inserted
within housing 124.
Height adjustment mechanism 40 is then inserted within chair base
socket 28 such that sensors 140 are in alignment with the switch
sensor mounted on chair seat 14. Wires (not shown) are routed to a
control mechanism switch (not shown) that is accessible by an
occupant sitting in chair seat 14 for selectively adjusting chair
seat height 30 with respect to chair base 12.
When the seated occupant engages the control mechanism switch to
raise chair seat 14 relative to chair base 12, electric motor 92
operates to rotate gear box 96. In one embodiment, the control
mechanism switch incorporates the battery life indicator. In an
alternative embodiment, housing 124 incorporates the battery life
indicator. Because gear box 96 is coupled to drive shaft 94, drive
shaft 94 rotates simultaneously with gear box 96. As drive shaft 94
is rotated, drive shaft threads 98 engage lower enclosure inner
threads 80 and cause lower enclosure member 44 to rotate. As lower
enclosure member 44 rotates, lower enclosure member outer threads
64 engage upper enclosure member threads 66 to cause upper
enclosure member 42 to rotate, thus raising chair seat 14 relative
to chair base 12.
FIG. 3 is a partial cut-away side view of an alternative embodiment
of a height adjustment mechanism 200 that may be used with chair 10
(shown in FIG. 1). Height adjustment mechanism 200 is similar to
height adjustment mechanism 40, shown in FIG. 2, and components in
height adjustment mechanism 200 that are identical to components of
height adjustment mechanism 40 are identified in FIG. 3 using the
same reference numerals used in FIG. 2. Accordingly, height
adjustment mechanism 200 includes drive mechanism 90, including
electric motor 92, drive shaft 94, and gear box 96. In addition,
height adjustment mechanism 200 also includes an upper enclosure
member 202 telescopically coupled to a lower enclosure member 204.
More specifically, lower enclosure member 204 is coupled
substantially co-axially to upper enclosure member 202 such that
lower enclosure member 204 telescopes into upper enclosure member
202. Upper enclosure member 202 is coupled between chair seat 14
(shown in FIG. 1) and lower enclosure member 204. Lower enclosure
member 204 is coupled between upper enclosure member 202 and chair
base 12 (shown in FIG. 1). In one embodiment, upper enclosure
member 202 and lower enclosure member 204 each have a substantially
circular cross-sectional profile. In an alternative embodiment,
upper enclosure member 202 and lower enclosure member 204 have
non-circular cross sectional profiles.
Upper enclosure member 202 includes an upper end 208 and a lower
end (not shown). Upper enclosure member upper end 208 is tapered to
be frictionally fit within a receptacle (not shown) extending from
chair seat 14. More specifically, upper enclosure member upper end
208 includes a chair control taper end 209. Chair control taper
ends 209 are known in the art. In one embodiment, upper enclosure
member upper end 208 also includes a spring (not shown) mounted in
such a manner as to provide a pre-determined amount of downward
travel of chair seat 14 when chair seat 14 is initially
occupied.
Upper enclosure member 202 includes a screw collar 210 and an
anti-screw collar 212. In one embodiment, screw collar 210 and
anti-screw collar 212 each have non-circular cross-sectional
profiles. In an alternative embodiment, screw collar 210 and
anti-screw collar 212 each have substantially circular
cross-sectional profiles. In a further embodiment, screw collar 210
has a substantially round cross-sectional profile and anti-screw
collar 212 has a substantially round inner cross-sectional profile
defined by an inner surface (not shown) of anti-screw collar 212,
and a non-circular outer cross sectional profile defined by an
outer surface 213 of anti-screw collar 212.
Screw collar 210 extends circumferentially around drive shaft 94
and is threadingly engaged by drive shaft 94. Accordingly, when
drive shaft 94 is rotated, screw collar 210 moves either towards
chair seat 14 or towards lower enclosure member 204 depending upon
a direction of rotation of motor 92 and drive shaft 94. Screw
collar 210 includes a plurality of anti-twist channels (not shown)
that extend lengthwise along screw collar 210. Screw collar 210
also includes a stop (not shown) adjacent an upper end (not shown)
of screw collar 210. The screw collar upper end is coupled to upper
enclosure upper end 208. The screw collar stop works in combination
with drive shaft stop 102 (shown in FIG. 2) to limit a distance
that upper enclosure member 202 may extend towards chair seat 14
from anti screw collar 212.
Anti-screw collar 212 also includes a plurality of anti-twist
channels 216. Anti-twist collar channels 216 extend radially inward
and mate with screw collar channels 214 to prevent screw collar 210
from rotating into anti-screw collar 212 when drive shaft 94 is
rotated. Additionally, an upper key washer 218 extends
circumferentially around anti-screw collar 212 and includes a
plurality of projections (not shown) that mate with anti-twist
collar channels 216 to prevent anti-screw collar 212 from rotating
with respect to screw collar 210. As a result, when drive shaft 94
is rotated, screw collar 210 either moves upward and away from
anti-screw collar 212 or moves towards anti-screw collar 212,
depending upon the rotational direction of drive shaft 94.
Furthermore, anti-screw collar 212 includes a stop flange adjacent
screw collar 210 that prevents anti-screw collar 212 from
over-rotating within anti-screw collar 212 and becoming stuck
against anti-screw collar 212 when drive shaft 94 is rotated.
Lower enclosure member 204 includes an upper end (not shown) and a
lower end 220. Lower enclosure member lower end 220 is tapered to
be frictionally fit within base center socket 28 (shown in FIG. 1).
More specifically, lower enclosure member lower end 220 includes a
swivel base socket 222 that permits chair seat 14 to rotate with
respect to chair base 12.
Lower enclosure member 204 also includes a lower screw collar 230
and an anti-screw collar 232. In one embodiment, screw collar 230
and anti-screw collar 232 have substantially non-circular profiles.
In an alternative embodiment, screw collar 230 and anti-screw
collar 232 have substantially circular profiles. Screw collar 230
extends circumferentially around drive shaft 94 and is threadingly
engaged by drive shaft 94. Accordingly, when drive shaft 94 is
rotated, screw collar 230 moves either towards chair base 12 or
towards upper enclosure member 202 depending upon a direction of
rotation of motor 92 and drive shaft 94. Screw collar 230 includes
a plurality of anti-twist channels (not shown) that extend
lengthwise along screw collar 230. Screw collar 230 also includes a
stop (not shown) adjacent a lower end (not shown in FIG. 3) of
screw collar 230. The screw collar lower end is coupled to lower
enclosure lower end 220. The screw collar stop works in combination
with a drive shaft stop (not shown) to limit a distance that lower
enclosure member 204 may extend towards chair base 12 from anti
screw collar 232.
Anti-screw collar 232 also includes a plurality of anti-twist
channels 216. Anti-twist collar channels 216 extend radially inward
and mate with the screw collar channels to prevent screw collar 230
from rotating into anti-screw collar 232 when drive shaft 94 is
rotated. Additionally, a lower key washer 238 extends
circumferentially around anti-screw collar 232 and includes a
plurality of projections (not shown) that mate with anti-twist
collar channels 216 to prevent anti-screw collar 232 from rotating
with respect to screw collar 230. As a result, when drive shaft 94
is rotated, screw collar 230 either moves upward and away from
anti-screw collar 232 or moves towards anti-screw collar 232,
depending upon the rotational direction of drive shaft 94.
Furthermore, anti-screw collar 232 includes a stop flange (not
shown) adjacent screw collar 230 that prevents anti-screw collar
232 from over-rotating within anti-screw collar 232 and becoming
stuck against anti-screw collar 232 when drive shaft 94 is
rotated.
Upper and lower enclosure members 202 and 204, respectively, extend
partially into a housing 240. Key washers 218 and 238 are between
housing 220 and respective screw collars 210 and 230. More
specifically, each key washer 218 and 238 is adjacent to an
exterior surface 242 of housing 240 at a respective upper side 244
and lower side 246 of housing 240. Housing 240 also includes an
inner surface 248 that defines a cavity 250. Upper and lower
enclosure members 202 and 204, respectively, extend partially into
housing cavity 250.
An upper and lower bushing 252 and 254, respectively, are each
within housing cavity 250 and adjacent each respective key washer
218 and 238. In one embodiment, bushings 252 and 254 are rubber
bushings. An upper and lower load bearing 256 and 258 are within
housing cavity 250 and are adjacent each respective bushing 252 and
254. Bearings 256 and 258, bushings 252 and 254, and upper and
lower enclosure members 202 and 204, respectively, are co-axially
aligned.
Gear box 96 is coupled to drive shaft 94 within housing cavity 250
between load bearings 256 and 258. More specifically, gear box 96
is coupled substantially perpendicularly to drive shaft 94. Gear
box 96 is also coupled to motor 92. A limit switch 260 is
electrically coupled to electric motor 92 and automatically stops a
flow of electric current to motor 92 when drive shaft 94 is rotated
to a height 30 (shown in FIG. 1) that is near a pre-set fully
extended position.
Housing 240 extends circumferentially around axis of symmetry 58
such that drive mechanism 90 is disposed within housing cavity 250.
Drive mechanism 90 is coupled to height adjustment mechanism 200
and receives power from rechargeable battery cells housed within
battery pack 144. Battery pack 144 is coupled to drive mechanism 90
with wires 146 which extend into housing 240 from a remote battery
housing 270. Battery pack 144 is also coupled to a resistance
sensing switch (not shown) which automatically stops a flow of
electric current to motor 92 when a pre-determined amount of
resistance is induced within height adjustment mechanism 200 as
chair seat height 30 (shown in FIG. 1) is adjusted. For example,
the resistance sensing switch automatically stops a flow of
electric current to motor 92 to prevent an occupant's legs (not
shown) from being compressed between chair seat 14 and an underside
(not shown) of a desk or table (not shown) as seat 14 is raised.
Additionally, battery pack 144 is coupled to a control mechanism
switch 272 that is accessible by an occupant sitting in chair seat
14. Control mechanism switch 272 permits selective adjustments of
the chair seat height 30 (shown in FIG. 1) to be made with respect
to chair base 12. In the exemplary embodiment, control mechanism
switch 272 is coupled to a battery life indicator 274 that
illuminates when the battery cells need recharging. In an
alternative embodiment, battery life indicator 274 sounds an
audible alarm when the battery cells need recharging.
During use, as drive shaft 94 is rotated in a first direction to
raise chair seat 14 both upper and lower enclosure screw collars
210 and 230 simultaneously move away from housing 240. More
specifically, upper enclosure member screw collar 210 is moved
towards chair seat 14, while lower enclosure member screw collar
230 is moved towards chair base 12. Reversing an operation of motor
92, reverses a rotation of drive shaft 94, and screw collars 210
and 230 move towards each other and towards housing 240 to lower
chair seat 14.
FIG. 4 is a cross-sectional view of swivel base socket 220. Swivel
base socket 220 is hollow and includes an opening 280 that extends
from an upper side 282 of swivel base socket 220 to a lower side
284 of swivel base socket 220. Opening 280 is sized to receive
screw collar 230. More specifically, a lower end 286 of screw
collar 230 extends into opening 280 and is circumferentially
surrounded by an insert 288. In one embodiment, insert 288 is a
Teflon.RTM. insert. Swivel base socket 220 is sized to provide side
loading resistance to height adjustment mechanism 200.
Screw collar lower end 286 includes a threaded opening 290 sized to
receive a fastener 292 used to secure screw collar to swivel base
socket 220. In one embodiment, fastener 292 is a shoulder screw.
Fastener 292 extends through a bushing 294 inserted into swivel
base opening lower side 284. Bushing 294 includes a shock
absorption spring 295 that is biased against fastener 292. Fastener
292 also extends through a hardened washer 296 and through a ball
bearing assembly 298 positioned between bushing 294 and screw
collar lower end 286.
FIG. 5 is partial cut-away side view of an alternative embodiment
of a height adjustment mechanism 300 that may be used with chair 10
(shown in FIG. 1). Height adjustment mechanism 300 is substantially
similar to height adjustment mechanism 200 shown in FIGS. 3 and 4,
and components in height adjustment mechanism 300 that are
identical to components of height adjustment mechanism 200 are
identified in FIG. 5 using the same reference numerals used in
FIGS. 3 and 4. Accordingly, height adjustment mechanism 300
includes drive mechanism 90, including electric motor 92, drive
shaft 94, and gear box 96. In addition, height adjustment mechanism
300 also includes an upper enclosure member 302 telescopically
coupled co-axially to lower enclosure member 304. Upper and lower
enclosure members 302 and 304, respectively are substantially
similar to upper and lower enclosure members 202 and 204.
Upper enclosure member upper end 208 includes taper end 209, and
lower enclosure member 304 includes anti-screw collar 232 and lower
screw collar 230 (shown in FIGS. 3 and 4). Lower enclosure member
lower end 220 also includes swivel base socket 222 and key washer
238. A stroke resistance spring 310 circumferentially surrounds
lower enclosure member 304 and is between key washer 238 and a
lower side 312 of a housing 314.
Gear box 96 is coupled to drive shaft 94 between bearings 256 and
258. More specifically, gear box 96 is coupled substantially
perpendicularly to drive shaft 94 adjacent an upper end 316 of
drive shaft 94. Limit switch 260 is electrically coupled to
electric motor 92 and automatically stops a flow of electric
current to motor 92 when drive shaft 94 is rotated to a height (not
shown) that is near a pre-set fully extended position.
Housing 314 is substantially similar to housing 240 (shown in FIGS.
3 and 4) and extends circumferentially around axis of symmetry 58
such that drive mechanism 90 is housed within housing 314. Drive
mechanism 90 is coupled within height adjustment mechanism 300 to
receive power from battery pack 144. Battery pack 144 is not housed
within housing 314, but is instead removably coupled to drive
mechanism with wires (not shown) which extend into housing 314 from
a separate battery housing 316. Battery pack 144 is also coupled to
a resistance sensing switch (not shown) which automatically stops a
flow of electric current to motor 92 when a pre-determined amount
of resistance is induced into height adjustment mechanism 300 as
chair seat height 30 (shown in FIG. 1) is adjusted. For example,
the resistance sensing switch automatically stops a flow of
electric current to motor 92 to prevent an occupant's legs (not
shown) from being compressed between chair seat 14 and an underside
(not shown) of a desk or table (not shown) as seat 14 is raised.
Additionally, battery pack 144 is coupled to a control mechanism
switch 320 that is accessible by an occupant sitting in chair seat
14. Control mechanism switch 320 permits selective adjustments of
chair seat height 30 to be made with respect to chair base 12. In
an alternative embodiment, battery pack 144 is coupled to motor 92
on an opposite side of gear box 96 than motor 92 is positioned.
Control switch 320 is coupled to housing 314. More specifically,
housing 314 includes an arm 322 that extends radially outward from
axis of symmetry 58, and is opposite electric motor 92 and battery
pack 144. Control switch 320 is coupled to an end 324 of arm 322.
In an alternative embodiment, housing 314 does not include arm 322
and control switch 320 is positioned remotely from housing 314 and
height adjustment mechanism 300. Because gear box 96 is coupled
substantially perpendicularly to drive shaft 94 at drive shaft
upper end 316, upper enclosure member taper end 209 is adjacent an
upper surface 328 of housing 314.
During use, as drive shaft 94 is rotated in a first direction to
raise chair seat 14, lower enclosure screw collar 230 is rotated by
drive shaft 94 and extends from housing 314 towards chair base 12.
Reversing an operation of motor 92, reverses a rotation of drive
shaft 94, and screw collars 230 moves towards housing 314, thus
lowering a relative position of chair seat 14.
FIG. 6 is a partial cut-away side view of an alternative embodiment
of a height adjustment mechanism 400 that may be used with chair 10
(shown in FIG. 1). FIG. 7 is an enlarged cross-sectional view of
height adjustment mechanism 400 taken along line 7--7. Height
adjustment mechanism 400 is substantially identical to height
adjustment mechanism 300 shown in FIG. 5, and components in height
adjustment mechanism 400 that are identical to components of height
adjustment mechanism 300 are identified in FIGS. 6 and 7 using the
same reference numerals used in FIG. 5. More specifically, height
adjustment mechanism 400 does not include control switch 320, but
rather upper enclosure member upper end 208 includes an actuation
switch 402 that is formed integrally with a taper end 404.
Upper enclosure member taper end 404 is hollow and includes an
opening 406 that extends from an upper surface 408 of taper end 404
to an internal surface 410 of taper end 404. Taper end 404 is
tapered and is co-axially aligned with respect to axis of symmetry
58. A lower side 411 of taper end 404 is threaded and couples to a
standard push button switch 412 included with known pneumatic
cylinders, such as are commercially available from Stabilius,
Colmar, Pa. A spring 413 is biased between push button switch 412
and actuation switch 402.
During use, when actuation switch 402 is depressed, spring 413 is
depressed into push button switch 412. Accordingly, because push
button switch 412 is electrically coupled to drive mechanism 90,
when button switch 412 is depressed, electric motor 92 is
activated, and remains activated as long as actuation switch 402
remains depressed. When actuation switch 402 is released and then
re-depressed, motor 92 reverses rotation, and chair seat 14 (shown
in FIG. 1) is moved in an opposite direction.
FIG. 8 is a cut-away side view of an alternative embodiment of a
height adjustment mechanism 500 that may be used with chair 10
(shown in FIG. 1). Height adjustment mechanism 500 is substantially
similar to height adjustment mechanism 400 shown in FIGS. 6 and 7,
and to height adjustment mechanism 40 shown in FIG. 2, and
components in height adjustment mechanism 500 that are identical to
components of height adjustment mechanisms 40 and 400 are
identified in FIG. 8 using the same reference numerals used in
FIGS. 2, 6, and 7. Accordingly, height adjustment mechanism 500
includes taper end 404 including actuation switch 402, drive
mechanism 90, and load bearing 106.
Height adjustment mechanism 500 also includes an upper enclosure
member 502 telescopically coupled to a lower enclosure member 504.
More specifically, lower enclosure member 504 is coupled
substantially co-axially to upper enclosure member 502 such that
upper enclosure member 502 telescopes into lower enclosure member
504. Upper enclosure member 502 is coupled between chair seat 14
(shown in FIG. 1) and lower enclosure member 504. Lower enclosure
member 504 is coupled between upper enclosure member 502 and chair
base 12. In one embodiment, upper enclosure member 502 has a
substantially circular cross-sectional profile.
Upper enclosure member 502 includes a hollow guide sleeve 506, an
upper end 508, and a lower end 510. In addition, upper enclosure
member 502 includes an outer surface 512 and an inner surface 514.
Guide sleeve 506 provides sideload resistance to height adjustment
mechanism 500. In addition, guide sleeve 506 includes a plurality
of anti-twist channels (not shown) that extend substantially length
wise along outer surface 512.
Upper enclosure member inner surface 514 defines a cavity 518.
Upper enclosure member cavity 518 has a diameter 520 measured with
respect to inner surface 514, and is sized to receive drive shaft
94 therein. More specifically, upper enclosure member inner surface
514 includes a plurality of threads 522 that extend radially inward
from inner surface 514 between an upper end 526 of upper enclosure
member 502 and a lower end 528 of upper enclosure member 502. As
drive shaft 94 is rotated into upper enclosure member cavity 518,
drive shaft threads 98 engage upper enclosure member threads 522
and threadingly couple upper enclosure member 502 to drive shaft
94.
Upper enclosure member outer surface 512 includes a plurality of
threads 530 that extend radially outward from outer surface 512
between upper enclosure member upper and lower ends 526 and 528,
respectively. Upper enclosure member 502 has an outer diameter 534
measured with respect to outer surface 512. Upper enclosure member
502 also includes a lower stop 540 adjacent to upper enclosure
member lower end 528.
Lower enclosure member 504 is hollow and includes an outer surface
541 and an inner surface 542 including a plurality of threads 544
which extend radially inward from inner surface 542. Inner surface
542 defines a cavity 546 that has a diameter 548 measured with
respect to inner surface 542. Lower enclosure member cavity
diameter 548 is larger than upper enclosure member outer diameter
534. Accordingly, lower enclosure member cavity 546 is sized to
receive upper enclosure member 502 therein. More specifically, as
upper enclosure member 502 is received within lower enclosure
member cavity 546, lower enclosure member threads 544 engage upper
enclosure member threads 530, such that lower enclosure member 504
is threadingly coupled to upper enclosure member 502.
Lower enclosure member 504 has an upper end 550 and a lower end
552. Lower enclosure member upper end 550 is threadingly coupled to
upper enclosure member 502. Lower enclosure member lower end 552 is
tapered to form a necked portion 554 that has an inner diameter
556. As a result, lower enclosure member necked portion diameter
556 is smaller than lower enclosure member cavity diameter 548.
Lower enclosure member outer surface 541 includes a plurality of
anti-twist channels (not shown) that extend between upper and lower
ends 550 and 552, respectively.
Lower enclosure member necked portion 554 is a distance 558 from
lower enclosure member lower end 552, and is sized to receive a
fitting 560. More specifically, because lower enclosure member
necked portion diameter 556 is smaller than lower enclosure member
cavity diameter 548, when fitting 560 is inserted into lower
enclosure member cavity 546 through lower enclosure member lower
end 552, fitting 560 must be forcibly compressed to be fully
inserted into lower enclosure member 504. More specifically, as
fitting 560 is inserted into lower enclosure member lower end 552,
necked portion 554 induces a compressive force into fitting 560. In
one embodiment, fitting 560 is press fit into lower enclosure
member lower end 552.
Fitting 552 includes a cavity portion 570, a shoulder portion 572,
and a coupling portion 574. Fitting cavity portion 570 is inserted
into lower enclosure member lower end 552 through lower enclosure
member necked portion 554. Fitting shoulder portion 570 has an
outer diameter 576 that is larger than lower enclosure member inner
diameter 556, and accordingly, fitting shoulder portion 570 limits
a depth 578 that fitting cavity portion 570 is inserted into lower
enclosure member 504.
Fitting coupling portion 574 extends radially outwardly from
fitting shoulder portion 572. More specifically, fitting coupling
portion 574 is co-axially aligned with respect to axis of symmetry
58 and extends substantially perpendicularly from fitting shoulder
portion 572 to couple with an outer housing 580 included with a
known pneumatic cylinder, such as are commercially available from
Stabilius, Colmar, Pa. More specifically, fitting coupling portion
574 extends from fitting shoulder portion 572 through a bearing
582, a hardened washer 584, and a rubber bushing 586 to a cylinder
clip 588. Cylinder clip 588 is known in the art and couples fitting
552 to housing 580. In one embodiment, bearing 582 is a ball thrust
bearing.
Housing 580 is known in the art and extends circumferentially
around height adjustment mechanism 500. More specifically, housing
580 extends circumferentially around upper enclosure member guide
sleeve 506. An insert guide 590 and an outer guide sleeve 592 also
extend circumferentially around upper enclosure member guide sleeve
506. Outer guide sleeve 592 is between insert guide 590 and upper
enclosure member guide sleeve 506, and insert guide 590 is between
outer guide sleeve 592 and housing 580.
Outer guide sleeve 592 provides additional sideloading support to
height adjustment mechanism 500 and includes a plurality of sleeve
pins 594 that extend radially inward from a lower end 596 of outer
guide sleeve 592. More specifically, upper enclosure member guide
sleeve 506 includes channels (not shown) that extend
circumferentially around guide sleeve 506 adjacent upper enclosure
member guide sleeve lower end 510. The upper enclosure member guide
sleeve channels are sized to receive outer guide sleeve pins 594,
and thus permit height adjustment mechanism 500 and chair seat 14
to rotate relative to chair base 12. In addition, insert guide 590
includes anti-rotational channels (not shown) which enable insert
guide 590 to mate with outer guide sleeve 592 to prevent outer
guide sleeve 592 from rotating with respect to housing 580.
Furthermore, a plurality of set screws 598 extend through housing
580 into insert guide 590.
A housing 600 extends circumferentially around axis of symmetry 58
such that upper enclosure member 502, lower enclosure member 504,
and drive mechanism 90 are enclosed within housing 600. In one
embodiment, housing 600 is fabricated from cast metal. In another
embodiment, housing 600 is fabricated from plastic. In addition,
housing 504 includes a receptacle 602 formed therein opposite motor
92 for receiving battery pack 144 therein. In one embodiment, taper
end 404 is formed unitarily with housing 600. In another
embodiment, receptacle 602 has a conical cross-sectional profile to
facilitate receiving battery pack 144 therein.
FIG. 9 is a side view of an exemplary embodiment of a battery pack
700 that may be used with adjustable chair 10 to provide power to a
height adjustment mechanism, such as height adjustment mechanisms
40, 200, 300, 400, and 500 (shown respectively in FIGS. 2, 3, 5, 6,
and 8). FIG. 10 is cross-sectional view of battery pack 700 taken
along line 10--10 (shown in FIG. 9). Battery pack 700 has a first
end 702, a second end 704, and a body 706 extending therebetween. A
housing 708 extends from battery pack first end 702 to battery pack
second end 704. In one embodiment, battery pack housing 708 has a
substantially elliptical cross-sectional profile. Alternatively,
battery pack housing 708 has a non-elliptical cross-sectional
profile. More specifically, housing 708 includes an upper portion
710 and a lower portion 712 separated by a gap 714 extending around
battery pack 700. In one embodiment, housing 708 is fabricated from
molded plastic. In the exemplary embodiment, housing lower portion
712 is covered with shrink wrap tubing (not shown).
A plurality of battery cells 720 are housed within a cavity 722
defined within battery pack housing 708. In one embodiment, battery
pack 700 includes only one battery cell 720. More specifically,
battery cells 702 are axially-aligned in an end-to-end relationship
within housing 708 to form an integrated battery pack 700. In the
exemplary embodiment, three battery cells 720 are housed within
battery pack housing 708. Alternatively, battery pack housing 708
may house more or less than three battery cells 720. A plurality of
spacer rings 724 extend circumferentially within battery pack
housing 708 to separate adjacent battery cells 720 such that
adjacent battery cells 720 are electrically coupled.
A plurality of fusible elements 730 are positioned radially inward
from each spacer ring 724. Adjacent battery cells 720 are
electrically coupled together through fusible elements 730. Fusible
elements 730 form an open circuit that prevents electrical current
from flowing between adjacent battery cells 720 when a preset
current flow is detected within fusible elements 730. More
specifically, when fusible elements 730 open, excessive electrical
current drains from battery cells 720 are stopped, thus reducing
potential damage to battery pack 700 or other components, such as
the height adjustment mechanism.
Each battery cell 720 includes a positive terminal 736 and an outer
casing 738 that is the negative terminal for each battery cell 720.
An opening 739 in battery pack housing 708 exposes a portion of
battery cell outer casing 738. Additionally, battery pack 700 has a
positive terminal 740 and a negative terminal 742. More
specifically, an opening 744 extending through battery pack housing
upper portion 710 exposes battery pack positive terminal 740.
Opening 744 extends along a side 746 of battery pack housing upper
portion 710 continuously across battery pack upper portion first
end 702 to a center (not shown in FIGS. 9 and 10) thereof. Battery
pack housing 708 provides insulation that prevents positive
terminal 740 from contacting 738 of a battery cell 720 adjacent
battery pack first end 702. Thus positive terminal 740 may be
accessed continuously from the center of battery pack 700 to a side
746 of battery pack 700.
Battery pack negative terminal 742 extends from a base 750 of a
battery cell 720 that is adjacent battery pack second end 704 to
battery pack housing upper portion 710. Negative terminal 742 is
insulated from battery cell casings 738 by housing 708, such that
additional insulating tape is not required. Furthermore, negative
terminal 742 is offset approximately ninety degrees from battery
pack positive terminal 740. In one embodiment, battery pack 700
provides approximately twelve volts of power to adjustable chair
10. In another embodiment, battery pack 700 provides greater than
twelve volts of power to adjustable chair 10. Alternatively,
battery pack 700 is sized to provide sufficient power to adjustable
chair for operation of controls (not shown) used in adjusting chair
10.
In the exemplary embodiment, battery pack housing 708 is formed of
two portions 760 and 762 coupled together in a clamshell-type
configuration. Portions 760 and 762 couple together around battery
cells 720 to form an integrated battery pack 700. More
specifically, housing portion 760 includes a projection 764 that
extends radially from housing portion 760. Projection 764 is
inserted into a mating slot 768 formed within housing portion 762.
Housing upper portion 710 also includes a projection and slot
combination (not shown in FIGS. 9 and 10) which work in combination
with housing lower portion projection and slot 764 and 768,
respectively, to couple housing portions 760 and 762 together.
A locking cap 770 is coupled to battery pack housing second end
704. More specifically, locking cap 770 includes a sidewall 772
extending circumferentially and substantially perpendicularly from
a base 774. Sidewall 772 and base 774 define a cavity 776 that has
a diameter 778 measured with respect to sidewall 772. Locking cap
cavity diameter 778 is slightly larger than an outer diameter 780
of battery pack housing 708 at battery pack second end 704.
Accordingly, battery pack housing 708 is received within locking
cap cavity 776. Locking cap 770 ensures battery pack housing
portions 760 and 762 remain coupled together.
A plurality of locking tabs 790 extend from locking cap 770. In the
exemplary embodiment, locking tabs 790 are T-shaped. Locking tabs
790 are beveled and are received within mating locking slots (not
shown) formed within height adjustment mechanism housing 124 (shown
in FIGS. 2, 3, 5, 7, and 8). More specifically, each locking tab
790 includes a first body portion 792 and a second body portion
794. First body portion 792 extends from locking cap 770 linearly
towards battery pack housing upper portion 710, and second body
portion 794 extends substantially perpendicularly from first body
portion 792 to form a T-shape. Accordingly, the mating locking
slots formed within chair 10 are also T-shaped in the exemplary
embodiment.
Locking tabs 790 removably couple battery pack 700 to height
adjustment mechanism housing 124. More specifically, because
locking tabs 790 may only be received within the mating locking
slots in one orientation, locking tabs 790 also ensure that battery
pack 700 is coupled to adjustable chair 10 in a proper alignment,
such that electrical connections between battery pack 700 and chair
10 are completed.
In the exemplary embodiment, locking cap 770 also includes a
plurality of raised ridges 798 to provide a surface for a user to
grasp during removal and installation of battery pack 700 to chair
10. In one embodiment, chair 10 includes an integrally formed
battery charger (not shown) that is selectively operable to
recharge battery cells 720. In another embodiment, battery pack 700
includes an integrally formed battery charger (not shown) that is
selectively operable after battery pack 700 is uncoupled from chair
10.
FIG. 11 is a top view of battery pack 700. Battery pack positive
terminal 740 is exposed through housing opening 744. Opening 744
extends along battery pack housing upper portion side 746
continuously across a portion 800 of battery pack upper portion
first end 702. More specifically, opening 744 extends from battery
pack housing upper portion side 746 through a center 802 of battery
pack 700 towards an opposite side 746 of battery pack upper portion
710. Housing upper portion 710 also includes a pair of projections
806 that extend through mating slots 808 in housing upper portion
710. Housing upper portion projections and slots 806 and 808,
respectively, work in combination with housing lower portion
projection and slot 764 (shown in FIG. 10) and 768 (shown in FIG.
10), respectively, to couple housing portions 760 and 762
together.
Battery pack negative terminal 742 is offset approximately ninety
degrees from battery pack positive terminal 740. Accordingly,
battery pack positive terminal 740 may be electrically coupled
within chair 10 (shown in FIG. 1) from battery pack side 746 or
battery pack end 702. Furthermore, in the exemplary embodiment,
battery pack negative terminal 742 may be electrically coupled
within chair 10 from battery pack side 746.
Locking cap locking tabs 790 extend radially outward from locking
cap 770 and from battery pack housing 708. More specifically,
locking tabs 790 removably couple battery pack 700 to chair 10.
Because locking tabs 790 may only be received within the mating
locking slots in one orientation, locking tabs 790 also ensure that
battery pack 700 is coupled to adjustable chair 10 in a proper
alignment, such that electrical connections between battery pack
700 and chair 10 are completed. In the exemplary embodiment,
locking cap 770 also includes a plurality of raised ridges 794 to
provide a surface for a user to grasp during removal and
installation of battery pack 700 to chair 10.
While the invention has been described in terms of various specific
embodiments, those skilled in the art will recognize that the
invention can be practiced with modification within the spirit and
scope of the claims.
* * * * *